Java

Using IMAP IDLE to Wait for Updates

This example demonstrates how to use the IMAP IDLE functionality in Chilkat. Chilkat2 Java

import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Imap;

public class ChilkatExample {

    public static void main(String[] args) {
        Imap imap = new Imap();

        // ....
        // ....
        // ....

        // Select an IMAP mailbox
        try {
            imap.selectMailbox("INBOX");

            // After a mailbox has been selected, IDLE may begin.
            // Idling tells the IMAP server to push unsolicited updates for the selected
            // mailbox to the connected client (which is your application).
            imap.idleStart();
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Once idling has started, your code still has to periodically check to see
        // if any updates have arrived.  However, this is significantly different
        // then what normally occurs when checking email.  The IdleCheck does NOT
        // send a message to the IMAP server.  It simply checks the connection to see
        // if any data has arrived.  If so, it can be consumed and the client (your app)
        // can react appropriately.

        // Note: It is recommended that idling only run for a max of 20 minutes before stopping and
        // re-starting the IDLE.  This is to maintain a minimum low level of activity so that
        // the IMAP server does not disconnect (which it may do if it considers the connection to
        // be truly inactive, i.e. forgotten).

        // To check the connection for IDLE updates, call IdleCheck.  The 1st argument indicates how
        // long we're willing to wait. We'll wait 1 millisecond:
        String idleResultXml = "";
        try {
            idleResultXml = imap.idleCheck(1);

            // See the online reference documentation for details regarding the XML that is returned.
            // Your application code would parse the XML to determine what action to take.
            // If the XML contains "<idle></idle>", then no updates are available and your application
            // would call IdleCheck again at some point in the future.

            // If updates are available, the IDLE must be terminated by calling IdleDone, like this:
            imap.idleDone();
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Once the IDLE is terminated, your application can make calls to fetch email, etc.
        // Any attempt to communicate with the IMAP server prior to terminating the IDLE will
        // result in failure.

        // IMPORTANT: Please realize that your application code will be structured differently than shown here.
        // The call to IdleCheck will likely be in a function/procedure that is periodically called
        // after the IdleStart has been called from some other location in your app.
    }
}